<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>js的array的map就是遍历每一个数并做处理</title>
</head>
<body>
<script type="text/javascript">
    window.onload=function () {
        var fuck=[1,2,3,4];
        fuck=fuck.map(value =>{return value*2});
        // 2,4,6,8
        alert(fuck);
    }

</script>
</body>
</html>